Electrochemical biosensors transduce biological interactions into detectable electrochemical signals. Biological recognitive markers (e.g. enzymes, aptamers, or antibodies) could be immobilized/integrated at the electrochemical interface to mediate the sensing procedure. However, complexity of chemical modifications and non-specific binding, reduced the reliability and commerciality of such biosensors. If label-free interactions could be applied between analytes and interface, usage of such sensors in wide variety of bio applications would be developed. Such binding must induce changing in electrochemical signal of redox reporter. Moreover, if the oxidative/reductive electrochemical responses of the analyte were unique for different biological transformations (such as metastatic progression states of a cancer cell), sensing patterns would be achieved without any requirements to complex fictionalizations.
Therefore, there is a need for a label-free electrochemical approach with a high precision and fast detecting capability to monitor and detect the electrochemical state variations of cancer cells under cancer treatments such as anticancer drugs treatments.